1. Field of the Invention
The present invention relates to a transmission control system of a vehicle and a vehicle including the same.
2. Description of the Related Art
There has been developed a transmission control device that controls an output of an engine at the time of a speed change in a vehicle including an automatic transmission (see JP 3008684 B, for example).
In the transmission control device of the automatic transmission described in JP 3008684 B, increasing the output of the engine at the time of down-shifting the automatic transmission with an accelerator being substantially tuned off suppresses a shift shock generated in the vehicle.
Such an output adjustment of the engine is performed using an electronic throttle system, for example. An opening of a throttle valve is quickly and appropriately adjusted by an actuator in the electronic throttle system. This allows an appropriate amount of air to be supplied to the engine and a combustion state of an air-fuel mixture in the engine to be stabilized. This results in lower fuel consumption of the engine and a cleaner exhaust gas.
In the foregoing electronic throttle system, however, the output adjustment of the engine cannot be performed in the case where the actuator does not operate due to any reason. Therefore, an electronic throttle system capable of mechanically and electrically adjusting the opening of the throttle valve has been developed in order to solve such a problem (see JP 2006-336639 A).
The electronic throttle valve system described in JP 2006-336639A includes the throttle valve, a controller, an electric motor and a guard mechanism. The electric motor is coupled to a valve stem of the throttle valve. The valve stem of the throttle valve is coupled to a throttle grip through the guard mechanism and a throttle cable.
In the electronic throttle valve system, the electric motor is electrically controlled by the controller according to an operation amount of the throttle grip. This causes the valve stem of the throttle valve to rotate and the opening of the throttle valve to be adjusted.
In addition, the guard mechanism is mechanically rotated according to the operation amount of the throttle grip. When the electric motor is not in operation, rotation of the guard mechanism is transmitted to the valve stem. Accordingly, the opening of the throttle valve can be adjusted even when the electric motor is not in operation.
In the throttle valve system described in JP 2006-336639 A, a rotation angle of the valve stem is restricted by the guard mechanism. Specifically, when the throttle grip is not operated by a driver, the valve stem can hardly be rotated.
Therefore, the output of the engine cannot be sufficiently increased when the throttle grip is not operated by the driver even though the throttle valve system described in JP 2006-336639 A is provided in the vehicle including the transmission control device described in JP 3008684 B, for example. In this case, the shift shock cannot be sufficiently suppressed, degrading a driving feeling of the vehicle.